Bristol-Myers Squibb’s Opdivo raised red flags when it failed a key confirmatory small-cell lung cancer trial in October. But detailed results out Thursday may still be enough to protect its approval in the field, executives say.

At the European Society of Medical Oncology Immuno-Oncology Congress in Geneva, the New Jersey drugmaker presented expanded results of the Checkmate-331 study, showing its agent had reduced the risk of death by just 14% among patients who had progressed after platinum-based chemo—not enough to reach the statistical significance threshold.

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Still, that 14% “is very consistent with what we’ve seen” in the third-line setting, where Opdivo currently boasts an approval, Sabine Maier, thoracic program development lead for BMS’s oncology unit, said in an interview. And “what’s more important than the response rate is actually the durability,” she said, pointing out that Opdivo’s median response of 8.3 months nearly doubled chemo’s 4.5 months.

BMS netted its conditional small-cell OK back in August based on phase 1/2 trial data, and industry watchers had looked to Checkmate-331 to back up the FDA’s decision. When news hit that that trial had missed its primary endpoint, analysts turned their attention to a first-line maintenance study, which also missed the mark, putting the approval in jeopardy.

The way Maier sees it, though, “from a clinical perspective, Checkmate-331 has exactly confirmed what we’ve seen in the third-line approval based on the response rate … and especially the durability of the response,” she said. "[O]f course, I can’t comment on how regulators may see that," she added.

For now, Bristol will have to hope they agree. The company is looking to rack up some niche lung cancer sales, particularly as its application for a front-line approval in non-small cell lung cancer—immuno-oncology’s largest market—stalls at the FDA.

Meanwhile, the pharma giant will also be delving deeper into the Checkmate-331 results, which suggested that certain subgroups may benefit more from Opdivo treatment—such as platinum-resistant small cell lung cancer patients, who saw the drug cut their risk of death cut by 29% versus chemo.

“Obviously, there will be much further exploration and there will be learnings we can take forward,” Maier said, adding that “there will be additional analysis from a translational perspective,” too.